What I can't figure out is why the hell do they no longer make those gauges so that a person can adjust it to make it accurate? I had a 50 year old Silca that could that, but none, not even the new Silca can be adjusted anymore. In fact from what I remember all floor pumps back then you could adjust the gauge accuracy by turning a screw either on the underside of the gauge or by twisting off the top glass part and the screw was right there next to the needle. This screw would adjust the spring and had marks of + and - so you knew which way to turn it. It is a spring, those things can change PSI readout from atmospheric changes to wear over time just as your bathroom scale will do. I did google check to see if any one made a gauge that can do that or if there were any way you can adjust one these days, nothing, I got nothing. We live in a throw away world, of course that is better for the environment and natural resources, so you either have to buy a new pump if the gauge goes bad or if that particular company makes a replacement gauge, or say screw it and use a separate handheld gauge.